Hot melt adhesive composition

ABSTRACT

An adhesive composition comprising a polymer, a tackifier, a wax and a plasticizing amount in the range of 5-40% by weight of 1,4-cyclohexane dimethanol dibenzoate.

This is a divisional of application Ser. No. 227,705filed Aug. 3, 1988, now U.S. Pat. No. 5,026,756.

BACKGROUND OF THE INVENTION

Hot melt adhesive compositions are typically thermoplastic materials which are solid at room temperature. When heated to a liquid or molten form, the hot melt adhesive can be applied to a first substrate. The hot melt adhesive can then join the first substrate together with a second substrate as the hot melt adhesive cools back to a solid.

Hot melt adhesives are generally composed of three components: (1) a polymer; (2) a tackifier; and (3) a wax.

The polymer provides strength and adhesive characteristics. The tackifier allows the polymer to be more adhesive by improving wetting during the application. The tackifier is typically necessary in preferred compositrions. The wax reduces the overall viscosity of the adhesive, thereby allowing the adhesive to liquify for a hot melt application at lower temperatures. The wax also controls the set time of the system--i.e. the time required to solidify the adhesive once the first and second substrates are compressed together.

Other components such as plasticizers are used in the formulation of hot melt adhesives for various applications. Plasticizers reduce the overall viscosity of the adhesive and promote flexibility and wetting. Typical types of plasticizers used are phthalates, glycolates, polybutenes, and mineral oil. See "Adhesive Bonding", Chap. 8 Hot-melt Adhesives, by Thomas Flanagan, at p. 8-3, published my MacMillan.

Waxes can adversely affect the adhesion characteristics of the polymer. In addition, waxes are not compatible with polymers with high vinyl acetate contents. Thus, plasticizers are used in some applications instead of waxes. Examples of plasticizers are given in U.S. Pat No. 4,745,026, such as dicyclohexyl phthalate.

Of particular importance is the change in heat, i.e. ΔH, as the hot melt adhesive changes from one phase to another. The lower the ΔH, the less heat is required to convert the solid adhesive to the liquid phase. ΔH is proportional to melt down rate, i.e., the rate of melt down of the adhesive from a solid phase to the liquid phase. Adhesives that melt down to a liquid phase quickly and easily can be used in faster manufacturing applications than adhesives with slower melt down rates. Therefore the lower the ΔH, and the faster the melt down rate, the easier the adhesive is to work with in manufacturing applications. See 1988 Hot Melt, "Thermal Analyses as a Predictor of Performance", by Ernest F. Eastman, published in 1988 TAPPI Conference Papers. ΔH values can be readily determined using Differential Scanning Calorimeters (Perkin-Elmer).

Another major factor in hot melt adhesive compositions is compatibility--i.e. the degree of solubility of one component in another. The greater the compatibility, the more uniform and homogeneous the adhesive, and the better the bond the adhesive will provide. The closer the solubility parameters of different components are to each other, the greater the compatibility. See "Some Factors Affecting the Solubility of Polymers", by P. A. Small, J. Appl. Chem., 3, Feb. 1953 (which teaches how to predict solubility parameters).

Compatibility is related to cloud point temperature. Cloud point temperature is the temperature at which a component begins to solidify or "cloud up" as it cools from a clear liquid phase to the solid phase. For example, for waxes, the cloud point is usually the melting point of the wax. Generally, the lower the cloud point temperature, the greater the compatibility. See "Adhesives and Coatings Manual" by National Distillers and Chemical Corporation (1983).

As previously mentioned, set time is the time required to solidify the adhesive once the first and second substrates are compressed together. Fast set times are desirable in most manufacturing applications. Generally, the higher the melting point, the crystallinity, and the viscosity, the faster the set time. Id. Open time is the time during which the adhesive is applied to the first substrate and remains sufficiently molten to effect a bond between the first and second substrates. Long open times are desirable in most manufacturing applications. Generally, the lower the melting point, the crystallinity, and the viscosity, the longer the open time. Id.

Thus, it is desirable to have a highly crystalline adhesive component that has both high-melting-point and low-melting-point characteristics.

The primary objective of the present invention is to provide a hot melt adhesive composition containing 1,4-cyclohexane dimethanol dibenzoate as a unique component. The physical properties of 1,4-cyclohexane dimethanol dibenzoate indicate that it would be an improvement over existing hot melt adhesive components such as dicyclohexyl phthalate. More specifically, 1,4-cyclohexane dimethanol dibenzoate provides shorter set times than dicyclohexyl phthalate without adversely affecting open times.

In addition, 1,4-chclohexane dimethanol dibenzoate has a slightly lower ΔH than dicyclohexyl phthalate. Although other solid benzoates may have a lower ΔH than 1,4-cyclohexane dimethanol dibenzoate, they tend to super cool. During the cool down cycle, these other solid benzoates that super cool remain liquid in the system and act as liquid plasticizers would act, i.e., resulting in longer open times and adversely affecting set times. 1-4, cyclohexane dimethanol dibenzoate is highly crystalline and does not super cool.

Furthermore, the 4,4-cyclohexane dimethanol dibenzoate would be very useful as a polyester hot melt modifier. The crystalline nature of the 1,4-cyclohexane dimethanol dibenzoate would contribute significantly to the properties of a polyester hot melt (e.g., faster set time, improved viscosity reduction, etc.). Further, the polyester hot melts containing the 1,4-cyclohexane dimethanol dibenzoate would be useful in applications not now possible without it. Polyesters are generally not compatible with waxes and are not easily modified by waxes. U.S. Pat. Nos. 4,172,824 and 4,340,526 teach that certain benzoates are of use in polyester hot melts. However, the cited benzoates are limited in nature due to their tendency to super cool. The 1,4-cyclohexane dimethanol dibenzoate is an improvement over these prior art benzoates.

The use of polyesters comprising 1,4-cyclohexane dimethanol as a hot melt adhesive when blended with certain monomeric ester plasticizers is taught in U.S. Pat No. 4,340,526. However, this patent does not teach the use of 1,4-cyclohexane dimethanol dibenzoate as a plasticizer in a hot melt adhesive cmposition.

SUMMARY OF THE INVENTION

It has now been discovered that a hot melt adhesive composition comprising a polymer, a tackifier, and a plasticizing amount of 1,4-cyclohexane dimethanol dibenzoate works well as a hot melt adhesive. More particularly, it has been discovered that a hot melt adhesive composition comprising ethylene vinyl acetate as the polymer, a tackifier, and a plasticizing amount of 1,4-cyclohexane dimethanol dibenzoate is a suitable hot melt adhesive. In the present invention, the adhesive comprises a range of about 5-40% by weight of 1,4-cyclohexane dimethanol dibenzoate. More preferably, the adhesive comprises a range of about 25-35% by weight of 1,4-cyclohexane dimethanol dibenzoate. Most preferably, the adhesive comprises about 30% by weight of 1,4-cyclohexane dimethanol dibenzoate.

It has also been discovered that a hot melt adhesive composition comprising a polymer, a tackifier, a wax, and a plasticizing amount of 1,4-cyclohexane dimethanol dibenzoate is suitable as a hot melt adhesive. In such a composition, the adhesive comprises a range of about 5-40% by weight of 1,4-cycloohexane dimethanol dibenzoate. More preferably, this adhesive comprises a range of about 8-25% by weight of 1,4-cyclohexane dimethanol dibenzoate. Most preferably, the adhesive comprises about 16.6% byh weight of 1,4-cyclohexane dimethanol dibenzoate.

In addition, based on solubility parameters, it is anticipated that 1,4-cyclohexane dimethanol dibenzoate would work well in hot melt adhesive formulations having other polymers, such as polyvinyl acetate, ethylene/vinyl acetate copolymer, block copolymers (styrene-isoprene-styrene, styrene-butadiene-styrene, styrene-isobutylene-styrene), polyvinyl chloride, polyvinyl chloride/polyvinyl acetate, polyurethanes, polyesters and polyamides. Specifically, the solubility parameter of 1,4-cyclohexane dimethanol dibenzoate is about 8.0. Comparison of this value with, for example, those listed on p. 76 of the P. A. Small article cited above, indicates that 1,4-cyclohexane dimethanol dibenzoate is compatible with many different polymers.

For example, it is known that glycerol tribenzoate functions very well in polyester hot melt applications. Since 1,4-cyclohexane dimethanol dibenzoate has a similar solubility parameter as glycerol tribenzoate, it would be expected that 1,4-cyclohexane dimethanol dibenzoate would also work well in polyester hot melt applications. It is expected that 1,4-cyclohexane dimethanol dibenzoate is advantageous over glycerol tribenzoate in that 1,4-cyclohexane dimethanol dibenzoate has a significantly higher melting point resulting in faster set times without adversely affecting open times.

Furthermore, it has been discovered that compared to prior art compositions, 1,4-cyclohexane dimethanol dibenzoate requires a lower amount of heat to change from its solid to its liquid phase, and provides faster set times without adversely affecting open times.

1,4-cyclohexane dimethanol dibenzoate has the following structure wherein the dimethanol dibenzoate groups can be cis or trans and the cyclohexane ring can have either a chair or boat configuration: ##STR1##

The following examples of the present invention demonstrate the advantages of the present invention over the prior art.

EXAMPLES

The Differential Scanning Calorimeter ("DSC") curves for 1, 4-cyclohexane dimethanol dibenzoate are depicted in FIG. 1. The curve shown is binodal and shows that this molecule has both high melting point and low melting point characteristics. The sharpness of the primary curve demonstrates that 1,4-cyclohexane dimethanol dibenzoate is highly crystalline. Because of the binodal curve, the melting point is at two different temperatures, namely about 123° C. at the primary curve and about 80° C. at the secondary curve. The ΔH is about 8.85 mcal/mg.

FIG. 2 is the DSC curve for a ethylene vinyl acetate compound Elvax 250 made by E.I. duPont de Nemours Company, having a melt Index of 22-28 and comprising 28% vinyl acetate.

FIG. 3 is the DSC curve for paraffin wax.

FIG. 4 is the DSC curve for microcrystalline wax.

FIG. 5 is the DSC curve for dicyclohexyl phthalate.

FIG. 6 is the DSC curve for triphenyl phosphate.

FIG. 7 is the DSC cukrve for glycerol tribenzoate.

FIG. 8 is the DSC curve for neopentyl benzoate.

FIG. 9 is the DSC curve for pentacrythritol tetrabenzoate.

FIG. 10 shows curves of thermal viscosity versus temperature for various adhesive compositions. FIG. 10 demonstrates the affect 1,4-cyclohexanol dimethanol dibenzoate has in decreasing the thermal viscodity of adhesive compositions. Thermal viscosity was determined using a Brookfield RVT Viscometer and Thermosel.

FIG. 11 shows curves of thermal viscosity versus temperature for two different adhesive compositions, one containing 1,4-cyclohexane dimethanol dibenzoate and one containing dixyclohexyl phthalate. FIG. 11 demonstrates that at a specific temperature, the composition containing 1,4-cyclohexane dimethanol dibenzoate has a lower thermal viscosity than the composition containing dixyclohexyl phthalate. Thermal viscosity was determined using a Brookfield RVT Viscometer and Thermosel.

TABLE I

Table I is a summary of stat taken from Graph I for the plasticizer of the present invention, 1,4-cyclohexane dimethanol dibenzoate and Graphs III-IX for prior art plasticizers and waxes.

As shown in Table I,1,4-cyclohexane dimethanol dibenzoate is the only adhesive component which had all the following advantageous characteristics:

Low ΔH, high melting point, high crystallinty as shown by the sharpness of the primary curve, and a binodal curve.

                  TABLE I                                                          ______________________________________                                         Plasticizer         Melting     Sharpness                                      Or        ΔH  Point       of Primary                                                                             Binodal                                Wax       (mcal/mg) (°C.)                                                                               Curve   Curve                                  ______________________________________                                         1,4-cyclohexane                                                                          8.85      80,123      extremely                                                                              Yes                                    dimethanol                      sharp                                          dibenzoate                                                                     Paraffin Wax                                                                             16.80     69          moderate                                                                               No                                     Micro-    16.60     64,80       not sharp                                                                              Yes                                    crystalline                                                                    Wax                                                                            Dicyclohexyl                                                                             9.94      70          moderate                                                                               No                                     Phthalate                                                                      Triphenyl 9.25      54          moderate                                                                               No                                     Phosphate                                                                      Glycerol  4.53      73          moderate                                                                               No                                     Tribenzoate                                                                    Neopentyl 5.09      54          moderate                                                                               No                                     Benzoate                                                                       Pentaerythritol                                                                          6.78      103         moderate                                                                               No                                     Tetrabenzoate                                                                  ______________________________________                                    

TABLE II

Table II shows cloud point temperatures (°F.) and consisting of a 1:1 mixture of various polymers containing vinyl acetate and various plasticizer benzoates, including in Column 4 for plasticizer 1, mixtures containing the adhesive component of the present invention, 1,4-cyclohexane dimethanol dibenzoate.

Table II shows that when the plasticizer 1,4-cyclohexane dimethanol dibenzoate constitutes 50% parts by weight of the adhesive composition, it acts much like a wax. Table II also gives an estimate on the upper limits of the % plasticizer in mixture with polymers before compatibility begins to become adversely affected. Thus, in the present invention the 1,4-cyclohexane dimethanol dibenzoate in the adhesive is preferably less than 50% parts by weight.

                                      TABLE II                                     __________________________________________________________________________     CLOUD POINT TEMPERATURE (°F.)/CONSISTENCY                               1:1 MIXTURE OF POLYMER AND PLASTICIZER                                                                       Plasticizer 2                                                                  1:1 Mixture                                                            Plasticizer 1                                                                          of dipropylene                                            Melt Index                                                                           % Vinyl                                                                               1,4-cyclohexane                                                                        glycol dibenzoate                                                                       Plasticizer 3                                                                          Plasticizer                                                                            Plasticizer 5           Ethylene Vinyl                                                                          Of the                                                                               Acetate in                                                                            dimethanol                                                                             and diethylene                                                                          Neopentyl                                                                              Glycerol                                                                               Pentaerythritol         Acetate Polymer                                                                         Polymer                                                                              the Polymer                                                                           dibenzoate                                                                             glycol dibenzoate                                                                       Benzoate                                                                               Tribenzoate                                                                            tetrabenzoate           __________________________________________________________________________     ELVAX 40W                                                                               48-66 40%    196°                                                                            <160     <160    <160    260                                           Cheesy, Smooth   Smooth  Smooth  Smooth                                        Plasticizer                                                                    Crystallized out                                         ELVAX 150                                                                               38-48 33%    210     <160     <160    262     >350                                          Cheesy  Smooth   Smooth  Smooth  Smooth                                        Plasticizer                                                                    Crystallized                                             ELVAX 150W                                                                              38-48 33%    230°                                                                            <160     <160    260     >360                    Anti Blocking         Cheesy  Smooth   Smooth  Smooth  Smooth                  Additive              Plasticizer                                                                    Crystallized                                             ELVAX 210                                                                               365-440                                                                              28%    262°                                                                            190      204     260     >360                                          Cheesy  Smooth   Smooth  Smooth  Smooth                                        Plasticizer                                                                    Crystallized                                             ELVAX 250                                                                               22-28 28%    210°                                                                            166      <160    260     >360                                          Cheesy  Smooth   Smooth  Smooth  Smooth                                        Plasticizer                                                                    Crystallized                                             ELVAX 260                                                                               53-67 28%    188°                                                                            <160     <160    265     >360                                          Cheesy  Smooth   Smooth  Smooth  Smooth                                                                         Not all went            __________________________________________________________________________                                                            in                 

TABLE III

Table III shows cloud point temperatures for various polymer/plasticizer or wax mixtures. M-8880 is microcrystalline wax with a melting point of 183° F. and R-0855 is a paraffin wax with a melting point of 153° F. Elvax 150, as already described in Table III is an ethylene vinyl acetate polymer with a melt index of 38-48 and a 33% vinyl acetate in the polymer. Table III demonstrates that adhesive compositions with 1,4-cyclohexane dimethanol dibenzoate and Elvax 150 had lower cloud point temperatures than similar mixtures with Elvax 150 and the M-8800 and R-0855 waxes. This data confirms that 1,4-cyclohexane dimethanol dibenzoate has greater compatibility with Elvax 150 than M-8880 and R-0855 waxes.

                  TABLE III                                                        ______________________________________                                         Polymer/       % of Polymer to                                                                              Cloud Point                                       Plasticizer or Wax                                                                            Plasticizer or Wax                                                                           Temp. °F.                                  ______________________________________                                         Elvax 150/1,4-cyclohexane                                                                     75/25         134°                                       dimethanol dibenzoate                                                          Elvax 150/1,4-cyclohexane                                                                     88/12         68°                                        dimethanol dibenzoate                                                          Elvax 150/M-8880                                                                              50/50         184°                                       Elvax 150/M-8880                                                                              75/25         152°                                       Elvax 150/M-8880                                                                              88/12         150°                                       Elvax 150/R-0885                                                                              50/50         164°                                       Elvax 150/R-0885                                                                              75/25         150°                                       Elvax 150/R-0885                                                                              80/12         142°                                       ______________________________________                                    

TABLE IV

Table IV shows cloud point temperatures for various polymers and other adhesive components. Elvax 250, as already described in Table II, is an ethylene vinyl acetate polymer with a melt index of 22-28 and 28% vinyl acetate in the polymer. Piccovar L60 is a low molecular weight, nonpolar, thermoplastic, alkylaryl hydrocarbon polymer modifier made by Hercules, Incorporated. Piccovar L60 has a density of 1.05 kg/L at 25° C., and a flashpoint of 243° C. Piccovar L60 has a melt viscosity of 1 poise at 129° C., 10 poises at 97° C., and 100 poises at 77° C. H-100 is a tackifier and is specifically a hydrocarbon resin made by Eastman Chemical Products, Inc. under the trade name "Eastotac H-100". H-100 has a melting point >185° F., and a specific gravity of 1.04. Table IV shows that M-8880 and R-0855 waxes have no lower cloud point temperatures and thus no better compatibility than 1,4-cyclohexane dimethanol dibenzoate in mixtures with Piccovar L60 and Elvax 250, and H-100.

In addition, Table IV shows that 1,4-cyclohexane dimethanol dibenzoate, when mixed with Elvax 250 has a lower cloud point temperature and greater compatibility than mixtures of M-8880 and R-0855 waxes with Elvax 250.

Furthermore, Table IV shows that in a mixture of Elvax 250, H-100, M-8880, and 1,4-cyclohexane dimethanol dibenzoate, as the ratio of 1,4-cyclohexane dimethanol dibenzoate to M-8880 increases the cloud point temperature decreases, thereby indicating greater compatibility.

                  TABLE IV                                                         ______________________________________                                                         Ratio of polymer                                                                             Cloud Point                                      Polymer/Other Components                                                                       to other components                                                                          Temp. (°F.)                               ______________________________________                                         Elvax 250/1,4-cyclohexane                                                                      50/50         210°                                      dimethanol dibenzoate                                                          Elvax 250/1,4-cyclohexane                                                                      75/25         140°                                      dimethanol dibenzoate                                                          Elvax 250/M-8880                                                                               75/25         186°                                      Elvax 250/R-0855                                                                               75/25         168°                                      Piccovar L60/Elvax 250/                                                                        33/33/33      160°                                      1,4-cyclohexane                                                                dimethanol dibenzoate                                                          Piccovar L60/Elvax 250/                                                                        33/33/33      160°                                      M-8880                                                                         Piccovar L60/Elvax 250/                                                                        33/33/33      160°                                      R-0855                                                                         Elvax 250/H-100/1,4-                                                                           33/33/33      160°                                      cyclohexane dimethanol                                                         dibenzoate                                                                     Elvax 250/H-100/M-8880                                                                         33/33/33      182°                                      Elvax 250/H-100/R-0855                                                                         33/33/33      160°                                      Elvax 250/H-100/M-8880/                                                                        33/20.5/20.5/25                                                                              178°                                      1,4-cyclohexane                                                                dimethanol dibenzoate                                                          Elvax 250/H-100/M-8880/                                                                        33/8/33/25    190°                                      1,4-cyclohexane                                                                dimethanol dibenzoate                                                          Elvax 250/H-100/M-8880/                                                                        33/33/8/25    163°                                      1,4-cyclohexane                                                                dimethanol dibenzoate                                                          ______________________________________                                    

TABLE V

Table V shows tensile strength and % elongation at break date for various adhesive compositions. Tensile strength was determined pursuant to ASTM D638-64T. Table V shows that in specific formulations, 1,4-cyclohexane dimethanol dibenzoate outperforms dicyclohexyl phthalate in terms of tensile strength and % elongation at break. Specifically, Table V shows formulas A.2 and A.8 have greater tensile strength than corresponding formulas B.2 and B.8. Table V also shows that formula C.1. has greater tensile strength and % elongation at break than corresponding formula D.1, and that C.4 has greater tensile strength than corresponding formula D.4.

                  TABLE V-A                                                        ______________________________________                                         Parts by Weight                  %                                                                        1,4-            Elon-                                                          cyclohexane                                                                             Tensile                                                                               gation                                   Elvax           M-8880                                                                               dimethanol                                                                              strength                                                                              at                                  No.  250     H-100   wax   dibenzoate                                                                              (psi)  break                               ______________________________________                                         1    100     --      --    --       847    400                                 2    75      --      --    25       423    54                                  3    50      --      --    50       128    10                                  4    75      --      25    --       514    28                                  5    50      --      50    --       721    20                                  6    30      30      --    30        69    10                                  7    30      30      30    --       540    20                                  8    30      30      15    15       603    26                                  9    30      15      15    30       172    10                                  10   30      --      30    30        53    10                                  ______________________________________                                    

                  TABLE V-B                                                        ______________________________________                                         Parts by Weight                                                                                           Dicyclo-                                                                              Tensile                                                                               %                                          Elvax           M-8880                                                                               hexyl  strength                                                                              Elongation                            No.  250     H-100   wax   phthalate                                                                             (psi)  at break                              ______________________________________                                         1    100     --      --    --     847    400                                   2    75      --      --    25     300    246                                   3    50      --      --    50     230    292                                   4    75      --      25    --     514    28                                    5    50      --      --    50     721    20                                    6    30      30      --    30     134    378                                   7    30      30      30    --     540    20                                    8    30      30      15    15     302    73                                    9    30      15      15    30     243    88                                    10   30      --      30    30     476    20                                    ______________________________________                                    

                  TABLE V-C                                                        ______________________________________                                         Parts by Weight                  %                                                                        1,4-            Elon-                                            Picco-        cyclohexane                                                                             Tensile                                                                               gation                                   Elvax   var     M-8880                                                                               dimethanol                                                                              strength                                                                              at                                  No.  250     L-60    wax   dibenzoate                                                                              (psi)  break                               ______________________________________                                         1    30      30      --    30       288    646                                 2    30      30      30    --       472    126                                 3    30      30      15    15       234    128                                 4    30      15      15    30       523     20                                 5    30      --      30    30        53     10                                 ______________________________________                                    

                  TABLE V-D                                                        ______________________________________                                         Parts by Weight                                                                             Picco-        dicyclo-                                                                              Tensile                                                                               %                                          Elvax   var     M-8880                                                                               hexyl  strength                                                                              Elongation                            No.  250     L-60    wax   phthalate                                                                             (psi)  at break                              ______________________________________                                         1    30      30      --    30     137     60                                   2    30      30      30    --     472    126                                   3    30      30      15    15     246    232                                   4    30      15      15    30     249    112                                   5    30      --      30    30     476     20                                   ______________________________________                                    

TABLE VI

Table VI shows cloud point temperatures for various adhesive compositions. Table VI shows that certain formulations having 1,4-cyclohexane dimethanol dibenzoate has the same cloud point temperatures and thus, the same compatibility as those of corresponding formulations containing dicyclohexyl phthalate. Specifically, A.10. through A. 13. has the same cloud point temperatures, and thus, the same compatibility as corresponding formulations B.10 through B.13.

                  TABLE VI-A                                                       ______________________________________                                         Parts by Weight                                                                                                 1,4-                                                               Picco-      cyclohexane                                                                             Tem-                                      Elvax           var   M-8880                                                                               dimethanol                                                                              perature                             No.  250     H-100   L-60  wax   dibenzoate                                                                              (°F.)                         ______________________________________                                         1    75      --      --    --    25       460                                  2    75      --      --    25    --       186                                  3    50      --      --    --    50       210                                  4    50      --      --    50    --       180                                  5    30      30      --    30    --       182                                  6    30      30      --    --    30       160                                  7    30      30      --    15    15       184                                  8    30      15      --    15    30       188                                  9    30      --      --    30    30       180                                  10   30      --      30    30    --       <160                                 11   30      --      30    --    30       <160                                 12   30      --      30    15    15       <160                                 13   30      --      15    15    30       <160                                 14   30      --      --    30    30       180                                  ______________________________________                                    

                  TABLE VI-B                                                       ______________________________________                                         Parts by Weight                                                                                     Picco-      dicyclo-                                                                              Cloud Point                                 Elvax           var   M-8880                                                                               hexyl  Temperature                            No.  250     H-100   L-60  wax   phthalate                                                                             (°F.)                           ______________________________________                                         1    75      --      --    --    25     <160                                   2    75      --      --    25    --      186                                   3    50      --      --    --    50     <160                                   4    50      --      --    50    --      180                                   5    30      30      --    30    --      182                                   6    30      30      --    --    30     <160                                   7    30      30      --    15    15     <160                                   8    30      15      --    15    30     <160                                   9    30      --      --    30    30     <160                                   10   30      --      30    30    --     <160                                   11   30      --      30    --    30     <160                                   12   30      --      30    15    15     <160                                   13   30      --      15    15    30     <160                                   14   30      --      --    30    30     <160                                   ______________________________________                                    

TABLE VII

Table VII shows temperature and viscosity data for various adhesive compositions. Table VII shows that as 1,4-cyclohexane dimethanol dibenzoate is substituted for tackifier H-100, the viscosity of the composition is dramatically reduced. Viscosity was determined using a Brookfield RVT Viscometer and Thermosel.

                  TABLE VII                                                        ______________________________________                                         Ratio of Parts by Weight Adhesive Components                                                         1,4-cyclohexane                                                                          Temper-                                        Elvax M-8880          dimethanol                                                                               ature  Viscosity                               250   wax     H-100   dibenzoate                                                                               (°F.)                                                                          (cps)                                   ______________________________________                                         1     1       1       --        250    1250                                                                    300    450                                                                     350    225                                     1     --      1       1         250    2650                                                                    300    950                                                                     350    425                                     1     1       --      1         250    525                                                                     300    275                                                                     350    175                                     1     .5      1       .5        250    1600                                                                    300    700                                                                     350    325                                     1     .5      .5      1         250    900                                                                     300    350                                                                     350    200                                     ______________________________________                                    

TABLE VIII

Table VIII shows set times and open times for two adhesive compositions, one containing 1,4-cyclohexane dimethanol dibenzoate and the other containing dicyclohexyl phthalate. This data shows that adhesive compositions with 1,4-cyclohexane dimethanol dibenzoate has faster set times and the same open time as a corresponding adhesive composition containing dicyclohexyl phthalate. Open times were determined pursuant to ASTM D4497-85. Set times were determined by the following test:

The adhesive and a drawdown bar were heated to 350° F. A 1.5 inch by 10 inch strip of 40 lb. Kraft paper was glued to a 40 lb. Kraft paper substrate using the drawdown bar to administer a 10 mil thick film and press the strip to the substrate. Immediately after application, the strip was peeled away from the substrate. The time at which 50% of the paper fiber tore was taken as the set time.

                                      TABLE VIII                                   __________________________________________________________________________     Ratio of Parts by Weight of Adhesive Components                                            1,4-cyclohexane                                                                               Set Open Set Open                                   Elvax                                                                              M-8880  dimethanol                                                                             dicyclohexyl                                                                          Temp.                                                                              Viscosity                                                                           Time                                                                               Time                                   250 wax H-100                                                                              dibenzoate                                                                             phthalate                                                                             (°F.)                                                                       (cps)                                                                               (sec)                                                                              (sec)                                  __________________________________________________________________________     1   1   1   --      --     250 1250                                                                       300 450       5                                                                350 225                                             1   --  1   1       --     250 2650                                                                       300 950      10                                                                350 425                                             1   1   --  1       --     250 525                                                                        300 275       5                                                                350 175                                             1   .5  1   .5      --     250 1600                                                                       300 700                                                                        350 325                                             1   .5  .5  1       --     250 900                                                                        300 350       5                                                                350 200                                             1   .5  1   --      .5     250 2200                                                                       300 725  44  15                                                                350 350                                             1   .5  1   .5      --     250 1600                                                                       300 575  35  15                                                                350 300                                             __________________________________________________________________________

TABLE IX

Table IX shows the cloud point temperatures and viscosity at specific temperatures for compositions containing 1,4-cyclohexane dimethanol dibenzoate. This table shows that 1,4-cyclohexane dimethanol dibenzoate works well as an adhesive component with polymers other than ethylene vinyl acetate. Kraton D1107 is made by Shell Chemical Corporation. Macromelt 6239 is made by Henkel Corporation. Viscosity was determined using a Brookfield RVT Visometer and Thermosel.

                                      TABLE IX                                     __________________________________________________________________________                    Parts by                                                                            Parts by Weight                                                                           Cloud Point                                           Type of  Weight                                                                              1,4-cyclohexane                                                                           temperature                                                                           Viscosity                                                                           Temp                                Polymer                                                                              Polymer  Polymer                                                                             dimethanol dibenzoate                                                                     °F.                                                                            (cps)                                                                               (°F.)                        __________________________________________________________________________     Kraton                                                                               Styrene-Isoprene-                                                                       75   25         160    9500 350                                 D1107 Styrene                                                                  Block          90   10         120    Too viscous to                           Copolymer                             be measurable                            Macromelt      75   25         <140   --   --                                  Polyamide      90   10         <140   --   --                                  6239                                                                           __________________________________________________________________________

                  TABLE X                                                          ______________________________________                                         Formulations for FIG. 10                                                       Ratio of Parts by Weight of Adhesive Components                                                             1,4-cyclohexane                                                                          Dicyclo-                                Formu- Elvax   M-8880        dimethanol                                                                               hexyl                                   lation 250     Wax     H-100 dibenzoate                                                                               phthalate                               ______________________________________                                         A      1       1       --    1         --                                      B      1       .5      .5    1         --                                      C      1       1       1     --        --                                      D      1       .5      1     .5        --                                      E      1       --      1     1         --                                      ______________________________________                                    

                  TABLE XI                                                         ______________________________________                                         Formulations for FIG. 11                                                       Ratio Of Parts By Weight Of Adhesive Components                                                             1,4-cyclohexane                                                                          Dicyclo-                                Formu- Elvax   M-8880        dimethanol                                                                               hexyl                                   lation 250     Wax     H-100 dibenzoate                                                                               phthalate                               ______________________________________                                         A      1       .5      1     .5        --                                      B      1       .5      1     --        .5                                      ______________________________________                                    

OTHER APPLICATIONS AND SUMMARY

Other components besides a polymer, a tackifier, and 1,4-cyclohexane dimethanol dibenzoate can be added to the adhesive compositions of the present invention.

It is expected that 1,4-cyclohexane dimethanol dibenzoate can be used in many other applications besides hot melt adhesive compositions. For example, it is believed that 1,4-cyclohexane dimethanol dibenzoate would work well in latex applications, powdered coating applications, and in heat reactive thermal delayed tack applications. In addition, it is expected that 1,4-cyclohexane dimethanol dibenzoate would work well as a thermoplastic process aid.

The foregoing detailed description of the invention has been made in general terms and with respect to several preferred embodiments. Many of the specific preferred materials, temperatures, and methods stated herein may be varied by persons skilled in the art without departing from the spirit and scope of this invention. Accordingly, the invention resides solely in the claims hereinafter appended. 

What is claimed is:
 1. A solid non-aqueous hot melt adhesive composition comprising a polymer, a tackifier, a wax, and a plasticizing amount in the range of about 5-40% by weight of 1,4-cyclohexane dimethanol dibenzoate. 